A variety of feeding adaptations and feeding habits have been identified in butterflies of North America. All butterflies feed on liquid, typically nectar produced by flowers. Butterflies have a proboscis or tongue in the form of a rolled up tube. For feeding, the tube is unrolled and nectar is forcibly drawn through the tube for drinking by the butterfly.
By way of example, larger butterflies such as the monarchs and swallowtails may have a proboscis or tongue up to 11/2" (3.8 cm) long. The tongues of frittillaries may reach 2" (5.0 cm). These butterflies prefer to feed down the tapered "tube" of tubular shaped flowers.
On the other hand smaller butterflies such as buckeyes, checker spots, sulfurs, skippers, blues, and painted ladies have shorter tongues. These butterflies prefer surface feeding on nectar from the surface of nectar producing parts of the flower. Yet other butterflies including red admirals, question marks, morning cloaks, and angelwings are known to feed on the sweet liquid produced by fermenting fruit.
A butterfly feeder is described in the Brown U.S. Pat. No. 5,269,258. The Brown butterfly feeder is generally supported by hanging but can be mounted on a post. A cover is placed over a peripheral annular configuration feeding trough filled with a sugar solution which may contain other enumerated ingredients. Holes are formed in the cover for proboscis feeding by butterflies apparently inserting the tongue through a hole in the cover and into the sugar solution. The cover is also formed with depressions for receiving rotting fruit for fermenting juice feeders.
A disadvantage of the Brown butterfly feeder described in U.S. Pat. No. 5,269,258 is the limited choice of feeding opportunities available for butterflies. For example a long tongue feeding butterfly may not be attracted by the flat holes in the cover of the butterfly feeder. No choice and no opportunity is available for smaller butterflies that prefer surface feeding of nectar directly on flower parts. Furthermore, rotting fruit may fall out of the depressions in the cover during a wind.